In known manner, a mechanical system may be equipped with a support, a shaft, and a bearing interposed between the support and the shaft for supporting and guiding the latter in rotation. The bearing may be formed by a radial contact bearing, comprising a fixed ring disposed in a housing of the support and a movable ring integral with the shaft. However, such a bearing is not optimized for certain applications, for example in a gearbox and/or in case of heavy loads. In this case, one uses a spherical bearing formed by a self-adjusting bearing, in which a ring is fixed while the other ring is tiltable. Such a bearing is used to compensate for any misalignment between the shaft axis and the axis of the housing formed in the support.
Furthermore, it is known to provide a mechanical system with an instrumented bearing for controlling its operating parameters, such as the speed of rotation of the shaft. Such a bearing usually comprises a sensor integral with the fixed ring and a target integral with the mobile ring, forming a relative rotation detection device between the rings.
WO-A-2010 064 088 describes an example of instrumented bearing. The bearing comprises an outer ring and an inner ring delimiting a rolling chamber in which is disposed a row of balls. The outer ring has an outer surface in form of a sphere portion, and in a similar manner the housing of the support has an inner surface in form of a sphere portion which is complementary with the one of the bearing, thereby forming a spherical bearing. A sensor is fixed to the support integral with the outer ring of the bearing, while a target is fixed to the inner ring of the bearing. In case of relative tilt between the rings of the bearing, there is a risk that the target impinges on the outer ring.